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shore-line of Desolate Bay is backed by an unbroken line of cliffs, probably 

 600 ft. to 700 ft. in height, and remarkable for the development of extensive 

 screes. These, which consist of angular blocks of greywaeke of all sizes, 

 descend to the tide-level line and add greatly to the quantities of detritus 

 which the sea is carrying down the coast. 



At High Rock Point, which is the southern horn of the crescentic 

 Desolate Bay, the last of the naked screes carries its quota of angular blocks 

 to sea-level, and south of this spot the screes are " fixed " by vegetation. 

 Here also the raised beach-ridge makes its first appearance, and extends 

 as a flat-topped terrace at the foot of the cliffs as far as Te Rewarewa Head. 

 North of Te Rewarewa the raised beach-ridge evidently rests upon the 

 surface of the raised shore-platform ; south of that headland it appears 

 to follow the outer margin of the latter. 



The most interesting development of the raised beach-ridges is found 

 just within the entrance of Porirua Harbour, on its eastern shore. In 

 its progress southward (prior, of course, to the uplift of 1855) the older 

 accumulation of travelling shingle extended in the form of detached beaches 

 or shingle-spits, piled up to 7 ft. above sea-level, right across the former 



INLAND KAHtOURAS 



MARLBOROUGH SOUNDS DISTRIC 



mountain: of western nelson 



Fig. 3. — Panoramic view of the entrance of Porirua Harbour, looking south-west and 

 west, showing the general topography and the relations hip of the shore- 

 line features. A, inland cliffs ; B, raised shore -plat form ; C, deltaic flat 

 of Taupo Creek ; the line of houses at Plimmerton marks the position of 

 the detached beach or spit which cut off the former Taupo indentation. 



indentations now represented by the flat-bottomed lower valleys of Spring 

 Creek, the Motuhara Stream, and Taupo Creek. (Compare figs. 4 and 5.) 

 Continuing southward, the travelling shingle was piled up by the waves 

 about sea-level and carried forward until it had reached the vicinity of the 

 present Paremata railway-bridge. Here its farther progress was arrested 

 by the strong currents caused by the ebb and flow of the tide in the 

 extensive Pahautanui arm of Porirua Harbour. 



The formation of this inner beach-ridge, which prior to the 1855 

 earthquake reached a maximum height of 8 ft. above high-tide level, was 

 succeeded by the formation of an outer detached beach or shingle-spit 

 (see fig. 5, at " The Narrows "), which branched off from the inner beach 

 at a spot half a mile south of Taupo Bay, and was built forward by the 

 waves as far as the present Paremata Point, when its farther progress was 

 again arrested by the tidal currents. Unable to extend longitudinally, 

 the spit was increased in breadth by additions of the travelling shingle 

 until it presented the appearance of three parallel ridges, the highest of 

 which was piled up to a height of 8 ft. above high-tide level. 



